The present invention relates generally to agricultural seeding implements, and more specifically to an opener assembly for accurately placing seeds a predetermined distance below the surface of the ground.
Numerous types of furrow opener assemblies are available for use with a grain drill or similar implement to place seed in a furrow below the surface of the ground. Some systems are relatively simple and use an opener tool connected to a pivotable press wheel arm so that the tool moves up and down with the press wheel. Such fixed systems have the disadvantage that the vertical relationship between the opener tool and the press wheel will change as the press wheel arm oscillates. Other designs, such as parallel linkage openers, are more complicated and expensive to fabricate, and the numerous pivots subject to wear can cause unwanted looseness in the system. Because a parallel linkage moves an opener vertically without rotation, trash shedding capability and durability in soils where rocks or other obstructions are present are usually much less than optimum.